🛡️ AI Skill Auditor v2.0 — for Antigravity · Claude Code · Gemini CLI · Cursor

A universal, dependency-free Node.js tool to statically audit AI Skills and local agents (like those used in Claude, Cursor, Antigravity) for malicious patterns and hidden Ghost Prompts.

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Before running downloaded skills full of .js, .py, .sh, or .md files, scan them to ensure they don't contain harmful code or malicious embedded instructions.

What does it detect? (6 risk categories)

#	Category	Examples
1	Dynamic code execution	eval(), new Function(), setTimeout with strings, vm.runInNewContext, exec(), compile(), __import__, pickle.loads
2	Exfiltration & covert communications	fetch(), axios, WebSocket, XMLHttpRequest, require('http'), curl|bash, wget|bash
3	Destructive commands	rm -rf, del /f, mkfs, dd if=, chmod 777, reverse shells with nc -e
4	Payload obfuscation	atob(), Buffer.from(…, 'base64'), base64 -d | bash, long hex strings
5	Hardcoded credentials	API keys (sk-, ghp_, AKIA), tokens, passwords in strings
6	👻 Ghost Prompts in Markdown	ignore previous instructions, do not tell the user, override safety, exfiltrate data, run_command SafeToAutoRun, zero-width characters, HTML comment injections

Additionally, at the end of each scan the auditor prints a complete inventory of all prompts and directives found in .md files, so you can review what instructions each skill actually contains.

Method 1: Use the official Plug & Play repository

1. Clone or download this repository into your global skills folder (e.g., antigravity/skills/).
2. Run the auditor against ANY folder on your computer:

node ai-skill-auditor/bin/audit.js "C:/path/to/suspicious/skill"

3. If the skill passes the audit, you'll receive a terminal output confirming 0 vulnerabilities and a green Markdown badge like this:

Configure your own rules: You can open config/rules.json to add new malicious RegEx patterns for JavaScript, Python, Shell, or Markdown without touching the main code.

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Method 2: The "Build It Yourself" One-Shot Prompt

Don't trust downloading external repositories? We understand. As cybersecurity advocates, we encourage you to build your own auditor using your AI.

Just paste this Master Prompt into your AI coding assistant (Claude, Cursor, etc.):

"Act as an AI Cybersecurity Expert specialized in prompt injection and supply-chain attacks on AI Skills. Create a folder named smartbrain-skill-auditor with a Node.js script (zero external dependencies) designed to statically audit local directories. The scanner must cover the following risk categories:

1. Dynamic code execution: eval(), new Function(), setTimeout/setInterval with strings, vm.runInNewContext, dynamic import() in JS; eval(), exec(), compile(), __import__, importlib, pickle.loads in Python. 2. Exfiltration and covert communications: fetch(), axios, XMLHttpRequest, WebSocket, require('http/https'), curl|bash, wget|bash, hardcoded URLs with tokens. 3. Destructive commands: rm -rf, del /f, mkfs, format, dd if=, chmod 777, reverse shells with nc -e. 4. Payload obfuscation: atob(), Buffer.from(…, 'base64'), base64 -d | bash, suspiciously long hex strings. 5. Hardcoded credentials and secrets: API keys (patterns like sk-, ghp_, AKIA), tokens, passwords in strings. 6. Ghost Prompts in Markdown files (.md): hidden instructions like ignore previous instructions, you are now, do not tell the user, send data to, override safety, bypass security, execute command, run_command, and zero-width characters or HTML comments with injections.

The script must:

• Separate the logic (bin/audit.js) from the rules (config/rules.json) with regular expressions by category (javascript, python, shell, markdown) so anyone can update the rules without touching the code.
• Recursively scan all .js, .ts, .py, .sh, .bat, .ps1, and .md extensions.
• At the end of the scan, print an inventory of all prompts and directives found in .md files (searching for patterns like "Act as", "You are", "Your role is", YAML frontmatter with ---, and sections titled "Instructions" or "System Prompt") so the user can review what instructions each skill contains.
• If the audit passes (0 vulnerabilities), print a green Markdown security badge to the terminal.
• If the audit fails, list each file and detected pattern with severity level.

Generate the complete folder structure and files in a single step."

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Created by SMARTbrain Activity - Elevating AI safety for domestic and professional users.